1. Field of the Invention
This invention relates generally to a fastening device, and more particularly to a magnetic locking apparatus of the type which includes two elements to be magnetically attached, wherein a first magnetic supply element both magnetically attracts the second element and engages it for being coupled therewith. When coupled together, the elements can resist all accidental external forces perpendicular to and parallel to the coupled surfaces.
2. Description of the Prior Art
There are known various types of devices using the magnetic attraction of a magnet for attaching two-part articles such as bags, clothes, shoes and the like. However, practically all such known devices depend solely upon the magnetic attraction which attaches their two component parts together, and therefore present disadvantages in that although the attraction between the device is relatively strong enough to resist external forces which are exerted parallel to the magnetic lines of force or perpendicular to the coupled surfaces of the two parts, such attraction tends to become less strong or resistant against forces across the magnetic lines of force or parallel to the surfaces, so that the two parts are easily displaced relative to each other and then disconnected. Those devices, which can resist the forces parallel to the magnetic lines of force, cannot overcome forces that are greater than the inherent magnetic attracting ability of the magnet. If the devices are to be made more resistant against such forces, they must employ costly, high-quality permanent magnets. This is not desirable from the aspect of economy. There are also known non-magnetic locking devices which accomplish the automatic locking function by means of a spring or an equivalent such as rubber, but those devices disadvantageously involve complex construction and improper working.